[custom_adv] Lopez and Anthony revealed their engagement on their Instagram feeds, respectively. The two have been together since 2017.The team at James Allen spoke with INSIDER, and estimated that the ring is a 15-carat diamond, and worth at least $1 million.Rare Carat estimated that it's a 20-carat ring, worth $4.5 million. [custom_adv] The $500,000 ring also has a micro-pavé platinum band and is engraved with "T ♡ S," which stands for Gaga's birth name, Stefani Germanotta. The couple split in summer 2016 and close sources are saying that she got to keep the ring. [custom_adv] This $500,000 heirloom might not be the most expensive ring on the list, but it's sentimental value is worth so much more. Princess Diana also wore this ring while she was engaged to Prince Charles. [custom_adv] It's worth approximately $1 million and even has some sentiment to it thanks to the fact that Theroux called on her good friend Jennifer Meyer to help design it.Sadly, the million-dollar ring wasn't enough to keep these two together. [custom_adv] The solitaire ring, which features side baguettes set in platinum, is worth $750,000. For someone who never thought they'd get married, Clooney sure did splurge. [custom_adv] Douglas did pretty good with this $1 million ring and their relationship isn't so bad either. The actors have been together for over 16 years. [custom_adv] The ring, which was designed by Brad and jeweler Robert Procop, is now a divorce diamond thanks to the couple's split in 2015. The divorce isn't final yet so who knows which one will walk away with the estimated $1 million ring. [custom_adv] The center oval diamond is surrounded by another six carats worth of diamonds and has been estimated to cost anywhere between $275,000 and $1.5 million.The couple split in 2012 when Katie started worrying that Tom would send their daughter Suri to a strict Scientology camp and the diamond hasn't been seen since. [custom_adv] The unique, yellow diamond is set in platinum and has two other diamonds on either side. The real kicker here is that this may be her second engagement ring. The tennis pro was spotted with an insane 11-carat, pear-shapedpink diamond back in 2001 which was easily worth up to $2.5 million dollars. [custom_adv] The center diamond was surrounded by 58 smaller pink diamonds and two half moon diamonds leading it to cost upwards of $2.5 million dollars. [custom_adv] The beautiful ring was given to her by her equally beautiful hubby, Ryan Reynolds, who had to have dropped at least $2.5 million on it. [custom_adv] Sadly, not even the most expensive engagement ring in Hollywood can help a couple live happily ever after. The wedding was called off after seven months. Luckily for Mariah, she legally gets to keep the $10 million ring since James was the one who broke it off. [custom_adv] The beautiful ring was given to her by her equally beautiful hubby, Ryan Reynolds, who had to have dropped at least $2.5 million on it. [custom_adv] The emerald cut diamond sits between two smaller diamonds and was designed by London Jeweler Graff. It's worth close to $3 million, which is practically pocket change for the family. [custom_adv] After her failed engagement to Ben Affleck, she gave the $2.5 million sparkler back. However, this ring, which is estimated to cost over $4 million, might've been sold according to rumors that started to spread after the couple's split back in 2011. [custom_adv] The $4.3 million ring goes on tour along with other accessories and mementos in the traveling exhibition "From Philadelphia to Monaco: Grace Kelly Beyond the Icon." [custom_adv] The flawless, cushion-cut diamond sits on a thin platinum band with micro-pavé diamonds and was created by Lorraine Schwartz, who also made the original 15-carat engagement ring.When this upgrade first appeared on the reality star's finger after Kanye closed a deal with Adidas, it was rumored to be worth $8 million. However, since the theft, lawyers and police officials have clarified that it's actually worth closer to $4.5 million. [custom_adv] The hotel heiress never made it down the aisle and stopped wearing the $4.7 million rock just four months after they initially announced their engagement. [custom_adv] Jay-Z gave her the center diamond set on a split shank band with micro-pavé diamonds in platinum. It set him back $5 million to finally put a ring on it. [custom_adv] The jaw-dropping $8.8 million ring was created by Elizabeth herself after Richard Burton, her 5th (and 6th) husband, bought the diamond for her at an auction. After setting it in platinum, she wore the ring every single day for the rest of her life.